1. Field of the Invention
The present invention relates to an apparatus and a method for producing ionic water, and a system and a method for producing electrolytic ionic water. Particularly, the present invention relates to a method and an apparatus for producing ionic water to be supplied to an apparatus for producing electrolytic ionic water used for cleaning a highly clean surface.
2. Description of the Related Art
Cleaning with electrolytic ionic water has recently been investigated for cleaning with higher cleanness. FIG. 4 shows an example of methods of producing electrolytic ionic water.
An electrolytic device 400 comprises an anode chamber 403 provided with an anode electrode 401, and a cathode chamber 404 provided with a cathode electrode 402, both chambers being separated by an ion exchange membrane 405. The electrolytic device 400 further comprises introduction pipe systems 406 and 407 for introducing raw water into the anode chamber 403 and the cathode chamber 404, respectively, and discharge pipe systems 408 and 409 for discharging electrolytic liquids from these chambers.
To the introduction pipe systems 406 and 407, respectively, electrolyte adding devices 410 and 411 are connected so as to continuously inject, for example, HCl, NH.sub.4 OH or the like, into the raw water. When an electric current is supplied directly to the electrodes 401 and 402 to continuously produce electrolytic reaction, electrolytic anode water and electrolytic cathode water each having a desired pH can continuously be obtained.
Although an electrolyte is added for effectively performing electrolysis or controlling the pH, the system shown in FIG. 4 requires the addition of an electrolyte which is diluted to a necessary concentration, and thus has the problem of requiring much time and the problem of causing variations in water supply to the electrolytic device due to the pulsation of a pump, and thus variations in electrolytic conditions, thereby causing difficulties in producing stable electrolytic ionic water. This method is also difficult to precisely add a low concentration (100 ppm or less) of electrolyte with good reproducibility. There are also problems with the occurrence of a collection of high-concentration liquid and the control of particles and the like.